My healthy 8 year old boxer boy past away yesterday only 30 hours after initial symptoms. It all began when I noticed he wasn't coming when I called him shortly after he had breakfast or his first of his 2 meals he gets per day. I went to check him and noticed he was not standing so I thought he was being lazy but when I picked him up whimpered. So I carefully grabbed him and I stood him up and noticed his back lefts were wobbly. Took to ER vet within the hour to see what was going on and after a very throrough exam Dr. said it appears as if he had a stroke. His legs were weak but able to stand and walk. He also had developed a twitch on his right eye. He was given a shot of anti-inflammatory, anti-anti-inflamatory pills to take and something for his stomach. ER vet sent home and said to bring back if condition worsen. We came back home and he peed and pooped and was still able to walk and stand on his own but laid him to rest. 3-4 hours later we noticed his gums were getting pale almost with a greenish tone and also legs have gotten weaker and more difficult for him to walk and get up so we decided we take him back. This time there is blood work and x-rays and he suspects something bursting. Doc said a tumor around his spleen may have ruptured very common in boxers and checking for bleeding and maybe cause of a clot. Blood work came back a bit off but within normal parameters. He said he was anemic but not necessarily loosing a lot of blood so he went to check x-rays and nothing in x-rays except he says his heart is too small for a boxer... So he wants to keep him over night and put an IV and oxygen therapy through the night... Come back next morning and he can no longer stand, he has an twitch on his lip and he can no longer see. So now is is also blind; he has lost his sight at this point. Gums pail, cold limbs, cold breath. So he says I need to take to a cardiologist and a neurologist ASAP (mind this is Sunday morning). The only thing he says he can do is oxygen therapy but that has not done much through the night as he has continued to worsen. So we take him home while we find him another place to go and we were afraid he died in the clinic. He was calm with a little bit of color on his gums but limbs still cold. So he says we can take him home and to try to keep him calm (mind this is a Sunday morning). We start making phone calls all over Miami and Broward County and of course as expected no specialty clinics are open, only ER vets. So we had him home for 4 hours gave him some pedialite tkeep hydrated and off we went to an animal hospital ER where he would get seen by a ER vet and neurologist the following morning. He stopped breathing 5 minutes after we put him in the car on the way to new ER. Tried to do CPR at no avail and ER clinic 20 minute drive. But... Wait... Let me rewind the tape. This dog has been jogging for 45 minutes with my wife the past 5 years every night. Large back yard and plays with is annoying boxer sister all day. And he has a small sick heart...?? There is more... This same week 4 days earlier, he was taken to his regular vet to check a small mass under his chin. He had had blood work, and full chest x-rays which radiologist says all normal. While I understand it could be a a matter of opinion but here is the dilema of a sick heart or not. That day he had an fine needle aspiration under sedation and all went well. I do not believe a sick heart would have stood sedation. So I started reading other deceases that could affect all this at one time. This all happened in less than 30 hours from initial symptoms. Could it be an aneurysm?Thank you.